feat: don't show sidebar by default for non-logged in user

[zeucapua]

Description

If the user is NOT logged in, the sidebar should not be showing by default. Vice versa if the user is logged in and in a large screen size.

Related Tickets & Documents

Closes #3573

Mobile & Desktop Screenshots/Recordings

Steps to QA

1. Go to the deploy preview

2. Ensure you are logged out AND you are in a large screen size

3. Remove the showingSidebar variable from the local storage via browser tools

4. Refresh and see the sidebar isn't showing

5. Do the same with a logged in user and see that the sidebar shows

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